Methods and apparatus for altering audio output signals

ABSTRACT

Methods, systems and computer readable media for altering an audio output are provided. In some embodiments, the system may change the original frequency content of an audio data file to a second frequency content so that a recorded audio track will sound as if a different person had recorded it when it is played back. In other embodiments, the system may receive an audio data file and a voice signature, and it may apply the voice signature to the audio data file to alter the audio output of the audio data file. In that instance, the audio data file may be a textual representation of a recorded audio data file.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent Application No. 61/010,079 filed on Jan. 3, 2008, the entirety of which is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

This is directed to altering audio output signals. More particularly, this invention relates to methods, systems and computer readable media for simulating one or more voices when playing back an audio file.

Media devices are widely used to play back various types of audio files, such as audiobook files, podcast files and music files. When using these devices, a user is limited to playing back the audio files as recorded. For example, when a user plays an audiobook file, the user can only listen to the originally recorded voice(s) of the narrator(s). Even if different narrators are used for different characters in the book, the voices of the narrators cannot be changed into different voices after the recording has been made.

Despite the restrictions involved in playing back audio files, users of media devices may wish to change the audio output of audio files. A mother, for example, might wish to change the narrator's voice in a pre-recorded, commercially available audiobook to her own voice, so that her child can listen to the audiobook as narrated in the mother's voice in her absence. In another scenario, a student listening to a lecture as a podcast file might want to change the audio of certain sections of the lecture to sound like someone else's voice, so as to emphasize important parts of the lecture.

The present invention solves these problems and others.

SUMMARY OF THE INVENTION

Methods, systems and computer readable media are provided for adjusting audio output signals. The system may include any suitable electronic device for producing audio output signals. The audio output signals produced may include vocal output signals.

In some embodiments, the system may receive an audio data file containing voice signals with an original or first frequency content as well as a second frequency content. The system may change the first frequency content of the voice to the second frequency content to produce an adjusted audio output.

In some embodiments, the system can utilize audio files containing given content having a first frequency characteristic corresponding to the spoken voice of one or more individuals. The system can also include a microphone or other input device such that a different audio signal characteristic of a different individual can be processed by the system. The system can then take the second audio signal and apply its characteristics to the first signal such that the given content can then be played back using the individual's voice characteristics without that individual ever having had to record the given content into the system.

In other embodiments, the system may receive a text of an audio data file and a voice signature. The system may produce an adjusted audio output of the audio data file by applying the voice signature to the text of the audio data file.

Persons of ordinary skill in the art will appreciate that at least some of the various embodiments described herein can be combined together or they can be combined with other embodiments without departing from the spirit of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features of the invention, its nature and various advantages will be more apparent upon consideration of the following detailed description, taken in conjunction with the accompanying drawings in which:

FIGS. 1 and 2 are illustrative systems that may be used in accordance with embodiments of the present invention;

FIG. 3 is a simplified schematic block diagram of an illustrative embodiment of circuitry in accordance with embodiments of the present invention;

FIGS. 4-8 are schematic views of illustrative displays in accordance with various embodiments of the present invention;

FIGS. 9A-9C are simplified logical flow diagrams of illustrative methods in accordance with embodiments of the present invention;

FIG. 10 is an illustrative audio data file structure in accordance with embodiments of the present invention; and

FIG. 11 is an illustrative metadata alter file structure in accordance with embodiments of the present invention.

DETAILED DESCRIPTION

FIG. 1 shows system 100. In some embodiments, such as that shown in FIG. 1, system 100 only includes handheld device 102. One skilled in the art would appreciate that various accessory devices (such as, e.g., headsets, docking stations, speaker systems, and others) could also be included in system 100.

Handheld device 102 can be any device that is capable of producing audio output signals including, but not limited to, a portable media player, an audiobook, an audio player, a video player, a cellular telephone, a computer, a stereo system, a personal organizer, a hybrid of such devices, or combinations thereof. Handheld device 102 may perform a single function (e.g., a device that plays music, such as the earlier versions of the iPod™ marketed by Apple Inc., or Apple's iPod™ Shuffle). Handheld device 102 may also perform multiple functions (e.g., a device that plays music, displays video, stores pictures, and receives and transmits telephone calls, such as an iPhone™ marketed by Apple Inc.).

Handheld device 102 is shown as including display component 104 and user input component 106. Display component 104 is illustrated in FIG. 1 as a display that is integrated into handheld device 102. Display component 104, like any other component discussed herein, does not have to be integrated into handheld device 102 and can also be external to handheld device 102. For example, display component 104 may be a computer monitor, television screen, and/or any other graphical user interface, textual user interface, or combination thereof. Display component 104 may present graphical displays, such as those discussed below in connection with FIGS. 4-8. Moreover, while device 102 is not shown with a speaker, persons killed in the art will appreciate that one or more speakers could be provided as integrated components in device 102, or as accessory components, such as headphones.

User input component 106 is illustrated in FIG. 1 as a click wheel. One skilled in the art would appreciate that user input component 106 could be any type of user input device that is integrated into or located external to handheld device 102. For example, user input component 106 could also be a mouse, keyboard, audio trackball, slider bar, one or more buttons, media device pad, dial, keypad, click wheel, switch, touch screen, any other input component or device, and/or a combination thereof. User input component 106 may also include a multi-touch screen such as that shown in FIG. 2 and described in commonly assigned Westerman et al., U.S. Pat. No. 6,323,846, issued Nov. 27, 2001, entitled “Method and Apparatus for Integrating Manual Input,” which is incorporated by reference herein in its entirety.

FIG. 2 shows computer system 200 which can also be used in accordance with the present invention. Computer system 200 includes media device 202. Media device 202 can be any device that is capable of producing audio output signals including, but not limited to, a portable media player, an audiobook, an audio player, a video player, a cellular telephone, a computer, a stereo system, a personal organizer, a hybrid of such devices, or combinations thereof. Media device 202 may perform a single function (e.g., a device that plays music, such as some of the earlier versions of the iPod™ marketed by Apple Inc. or Apple's iPod™ Shuffle). Media device 202 may also perform multiple functions (e.g., a device that plays music, displays video, stores pictures, and receives and transmits telephone calls, such as Apple's current line of iPod™ products and the iPhone™ marketed by Apple Inc.).

Media device 202 comprises user interface component 204. User interface component 204 is shown in FIG. 2 as a multi-touch screen that can function as both an integrated display and user input device. Media device 202 can also include one or more other user interface components, such as button 206, which can be used to supplement user interface component 204.

Microphone 208 and audio output 210 are respective examples of input and output components that can be integrated into media device 202. Audio output 210 is shown as being a speaker integrated into media device 202, but one skilled in the art would appreciate that an external device (such as headphones or any other accessory device, including wireless devices such as Bluetooth earpieces) or a connector can be used to facilitate the playing back of audio files and/or the audio portion of video and other multi-media files.

FIG. 3 illustrates a simplified schematic diagram of circuitry that can be implemented in a media device or devices, such as those discussed above in accordance with embodiments of the present invention. Media device 300 can include control processor 302, storage 304, memory 306, communications circuitry 308, input/output circuitry 310, display circuitry 312 and/or power supply 314. One skilled in the art would appreciate that, in some embodiments, media device 300 can include more than one of each component or circuitry, and that to avoid over-complicating the drawing, only one of each is shown in FIG. 3. In addition, one skilled in the art would appreciate that the functionality of certain components and circuitry can be combined or omitted and that additional components and circuitry, which are not shown in FIG. 3, can be included in media device 300.

Processor 302 can be configured to perform any function. Processor 302 may be used to run operating system applications, firmware applications, media playback applications, media editing applications, and/or any other application.

Storage 304 can be, for example, one or more storage mediums, including for example, a hard-drive, flash memory, permanent memory such as ROM, any other suitable type of storage component, or any combination thereof. Storage 304 may store, for example, media data (e.g., audio data files), application data (e.g., for implementing functions on device 200), firmware, wireless connection information data (e.g., information that may enable media device 300 to establish a wireless connection), subscription information data (e.g., information that keeps track of podcasts or audio broadcasts or other media a user subscribes to), contact information data (e.g., telephone numbers and email addresses), calendar information data, any other suitable data, or any combination thereof. The data may be formatted and organized in one or more types of data files.

Memory 306 can include cache memory, semi-permanent memory such as RAM, and/or one or more different types of memory used for temporarily storing data. Memory 306 can also be used for storing data used to operate media device applications.

Communications circuitry 308 can permit device 300 to communicate with one or more servers or other devices using any suitable communications protocol. For example, communications circuitry 308 may support Wi-Fi (e.g., a 802.11 protocol), Ethernet, Bluetooth™ (which is a trademark owned by Bluetooth Sig, Inc.), high frequency systems (e.g., 900 MHz, 2.4 GHz, and 5.6 GHz communication systems), infrared, TCP/IP (e.g., any of the protocols used in each of the TCP/IP layers), HTTP, BitTorrent, FTP, RTP, RTSP, SSH, any other communications protocol, or any combination thereof.

Input/output circuitry 310 can convert (and encode/decode, if necessary) analog signals and other signals (e.g., physical contact inputs (from e.g., a multi-touch screen), physical movements (from, e.g., a mouse), analog audio signals, etc, into digital data. Input/output circuitry can also convert digital data into any other type of signal or vice-versa. The digital data can be provided to and received from processor 302, storage 304, memory 306, or any other component of media device 300. Although input/output circuitry 310 is illustrated in FIG. 3 as a single component of media device 300, a plurality of input/output circuitry can be included in media device 300 (as discussed above). Input/output circuitry 310 can be used to interface with any input or output component, such as those discussed in connection with FIGS. 1 and 2. For example, media device 300 can include specialized input circuitry associated with (e.g., one or more microphones, cameras, proximity sensors, accelerometers, ambient light detectors, etc.). Media device 300 can also include specialized output circuitry associated with output devices such as, for example, one or more speakers, etc.

Display circuitry 312 can accept and/or generate signals for presenting media information (textual and/or graphical) on a display such as those discussed herein. For example, display circuitry 312 can include a coder/decoder (CODEC) to convert digital media data into analog signals. Display circuitry 312 also can include display driver circuitry and/or circuitry for driving display driver(s). The display signals can be generated by processor 302 or display circuitry 312. The display signals can provide media information related to media data received from communications circuitry 308 and/or any other component of media device 300. In some embodiments, display circuitry 312, like any other component discussed herein, can be integrated into and/or electrically coupled to media device 300.

Power supply 314 can provide power to the components of device 300. In some embodiments, power supply 314 can be coupled to a power grid (e.g., a wall outlet, automobile cigarette lighter, etc.). In some embodiments, power supply 314 can include one or more batteries for providing power to a portable media device. As another example, power supply 314 can be configured to generate power in a portable media device from a natural source (e.g., solar power using solar cells).

Bus 316 can provide a data transfer path for transferring data to, from, or between control processor 302, storage 304, memory 306, communications circuitry 308, and any other component included in media device 300.

In some embodiments, media device 300 may be coupled to one or more other devices (not shown) for performing any suitable operation that may require media device 300 and any other device to be coupled together. Media device 300 may be coupled to a host, slave, master and/or accessory device. The other device may perform operations such as data transfers and software or firmware updates. The other device may also execute one or more operations in lieu of media device 300 when, for example, memory 306 does not have enough memory space, or processor 302 does not have enough processing power to perform the operations efficiently. For example, if media device 300 is required to alter the audio output of an audio data file that is too large to be stored in memory 306, another device that is coupled to media device 300 may execute the alteration.

Alternatively, the other device may perform one or more operations in conjunction with media device 300 so as to increase the efficiency of media device 300. For example, if media device 300 needs to perform several steps in a process, media device 300 may execute some of the steps while the other device executes the rest.

The other device may be a device that is capable of functioning like media device 300 (e.g., a device that is capable of altering and producing audio outputs). In some embodiments, a plurality of media devices may be coupled to another device, and may share data using the other device as a server.

Media device 300 may be coupled with another device over a communications link using any suitable approach. As an example, the communications link may be any suitable wireless connection. The communications link may support any suitable wireless protocol such as, for example, Wi-Fi (e.g., a 802.11 protocol), Bluetooth®, infrared, GSM, GSM plus EDGE, CDMA, quadband, or any other suitable wireless protocol. Alternatively, the communications link may be a wired link that is coupled to both media device 300 and the other device (e.g., a wire with a USB connector or a 30-pin connector). A combination of wired and wireless links may also be used to couple media device 300 with another device.

FIGS. 4-8 are illustrative displays which may be presented to a user by a media device, such as the media devices discussed above, in accordance with various embodiments of the present invention. The displays shown in FIGS. 4-8 may be presented to a user in response to, for example, the media device being activated (e.g., turned ON or awakened from a sleep mode), receiving a user selection of a display option, receiving a signal from a remote device, and/or any other stimuli.

When presented with displays, a user can provide inputs to the media device using any suitable user input mechanism. As an example, a user may use an input mechanism to move a highlight region over an option on a display so as to send an instruction to the media device to select the option. As another example, the user may use an input mechanism to move a display icon over an option to choose the option.

The displays in FIGS. 4-8 may be divided into one or more regions. For example, FIG. 4 shows display 400 which includes information region 402, header region 404 and options region 406. Different embodiments of the inventions, may include more or less display regions.

Information region 402 may include information generated from data stored in memory of the media device. In some embodiments, animated and/or static icons can also be included in information region 402. Header region 404 may include a display title that helps a user understand the information available in options region 406. For example, header region 404 as shown in FIG. 4, can include a display title that identifies the information in region 406 as “Options”. The playback options available to the user when the media device is playing back an audio track, in this case, are “Play”, “Stop”, “Pause”, “Rewind”, etc.

As shown in FIG. 4, the currently selected option in region 406 is Pause option 408. Other options that are relevant to the discussion of one or more embodiments of the present invention can include audio track option 410 and select a voice option 412. One skilled in the art would appreciate that the options included in region 406, or any other region of a display in the present invention, could be arranged and grouped in any manner, including a vertical list or a two-dimensional table. Information region 402 may be updated automatically as the user navigates through the list of options. For example, options region 406 is shown with pause option 408 highlighted and corresponding information (e.g., an icon and the time the audio track playing was paused) being presented in information region 402.

The media device may allow a user to select an audio track whose audio output signals the user wishes to adjust. For example, FIG. 5 shows display 500 that the media device may present to a user in response to receiving a user selection of alter an audio track option 410. Display 500 may include selectable audio track options associated with alter an audio track option 410. For example, options region 502 includes audio track 1, audio track 2 and audio track 3. Any suitable number of audio track options may be presented in options region 502. In addition, display 500 may also include a region (as shown) that includes the start and end times for a given selected track.

Audio track 1, audio track 2 and audio track 3 may be associated with audio files that are accessible by the media device. The media device may receive a user selection of an audio track option if a user wishes to alter the audio output signals of the audio file that corresponds to the audio track option. Audio track 1, audio track 2 and audio track 3 may also be associated with one or more sections of an audio file. As an example, an audio track option may be associated with a section of an audio file that corresponds to a section of a recorded lecture (e.g., a section that includes information on a particular subject). As another example, an audio track option may be associated with all the sections of an audiobook file that include a voice recording for a character in the audiobook. The media device may receive a user selection of an audio track option that is associated with one or more sections of an audio file if a user wishes to alter the audio output of the one or more sections of the audio file that corresponds to the audio track option.

Once the media device has received a user selection of an audio track, the media device may also allow the user to select a voice option that the media device can use to alter the audio output of the audio track. For example, in response to a user selection of select a voice option 412 of FIG. 4, the media device may present display 600. Display 600 may include one or more selectable options associated with select a voice option 412. For example, options region 602 in display 600 may include selectable options such as a “female voices” option 604, a “male voices” option 606, a “celebrity voices” option 608, an “accents” option 610 (for voices with different accents), an “emotions” option 612 (for voices with different emotions), a “use my voice” option 614, a “download a voice” option 616 and/or other voice options that, when selected, can alter the pre-recorded voice(s) when playing back a given prerecorded audio file. Option region 602 may include any other suitable voice options.

Each voice option listed in options region 602 may be associated with one or more metadata alter files, which may contain information that describes the voice option. For example, the metadata alter files may be similar to the metadata alter file discussed below in connection with FIG. 11. In response to receiving a user selection of a voice option, the media device may establish that the voice option has been selected by the user. For example, the media device may establish a tag in the corresponding metadata alter file to indicate a user selection.

The media device may receive a user selection of a voice option listed in options region 602 if a user wishes to use a voice associated with the voice option to alter the audio output signals of an audio file. In response to a user selection of any of the voice options listed in options region 602, the media device may present the user with other selectable options that are associated with the selected voice option. As an example, after receiving a user selection of female voices option 604, the media device may present selectable voice options that are associated with different female voices (e.g., the voices of a baby, a girl, a teenager, a young woman, an elderly woman, or any other suitable female voice option). As another example, in response to receiving emotions option 612, the media device may present selectable voice options that are associated with voices that express different emotions (e.g., voices that convey happiness, sadness, anger, or any other emotion).

The media device may also receive a user selection of “download a voice” option 616, if a user wishes to access a voice from a database remote from the media device. In response to receiving “download a voice” option 616, the media device may communicate with the another device that the media device is coupled to so as to transfer the metadata alter files associated with the user selected voice option from the other device to the memory of the media device. In some embodiments, the media device may ask for a user selection of a device the user wants to access a voice option from if the media device is coupled to more than one other device. The media device may communicate with other devices using any of the communications techniques discussed above in connection with FIG. 3.

FIG. 7 shows display 700, which includes selectable celebrity voice options that may be presented to a user in response to a user selection of “celebrity voice” option 606. As shown in FIG. 7, options region 702 in display 700 may include selectable options such as a “Paul McCartney” option 704, a “Madonna” option 706, and an “Oprah” option 708.

Instead of selecting one of the available celebrity voices listed in options region 702, the user may decide to select a different voice option. Choosing “different voice” option 710 may allow the user to navigate from display 700 to a display with different voice options so the user can select a different voice option. As an example, in response to receiving a user selection of different voice option 710, the media device may present the user with a display that includes other voice options besides the voice options listed in display 700 (e.g., display 600, FIG. 6).

The media device may allow a user to record the user's voice, and to use the recorded voice to alter audio data files. For example, in response to receiving a user selection of the “my voice” option (e.g., “my voice” option 606, FIG. 6), the media device may present the user with display 800 shown in FIG. 8. Display 800 may include several selectable options for recording a user's voice. For example, options region 802 may include selectable options such as “record” option 804, “stop recording” option 806, “replay recording” option 808 and “delete recording” option 810.

In response to receiving a user selection of “record” option 804, the media device may execute a recording process associated with “record” option 804. The recording process may include capturing the voice signals produced by a user, and storing information describing the voice signal in a metadata adjust file. For example, the media device may record a user's voice signals using the process 900 discussed below in connection with FIG. 9C.

After selecting record option 804, the user may select “stop recording” option 806 at any time during the recording process. In some embodiments, if the media device receives “stop recording” option 806 while executing a step associated with “record option” 804, the media device may instantly terminate the execution of the step so as to terminate the recording process. In other embodiments, if the media device receives “stop recording” option 806 while executing a step associated with “record” option 804, the media device may finish performing the step before terminating the recording process.

When the media device has finished recording voice signals, the media device may play back the voice signals in response to a user selection of “replay recording” option 808. The media device may also receive a user selection of “delete recording” option 810 if the user wishes to delete a recorded voice. In response, the media device may remove the voice recording information that is stored in a metadata adjust file.

Instead of recording, replaying or deleting a voice, the user may decide to select a different voice option. The user may select “different voice” option 812 to do this. In response to receiving a user selection of “different voice” option 812, the media device may present the user with a display with different voice options (e.g., display 600, FIG. 6).

In accordance with some embodiments of the present invention, at least two approaches may be used to alter the audio output signals of an audio data file. In one approach, the media device may change the original frequency of an audio data file to produce audio output signals containing a second frequency value. In another approach, the media device may apply a voice signature to a text of an audio data file to produce altered audio output signals. The two approaches may be generalized as shown in FIGS. 9A-B. Process 900 begins at step 902. At step 904, the media device may be activated (e.g., turned ON or awakened from a sleep mode) either automatically or in response to a user interaction or a command from another device. For example, the media device can be an iPod™ that is powered down until a user interacts with, for example, by depressing its click wheel. As another example, the media device could be a cellular telephone that is activated in response to receiving a wireless signal from a cellular telephone tower.

Once the media device is activated, the circuitry of the media device may present a display to the user at step 906. The display presented may include options available to the user which are related to the function the media device is performing or is about to perform.

At step 908, the media device waits for a user interaction. The user may interact with the media device using an input component, device or by any other means. For example, the user may interact with the media device using the input components discussed above in reference to FIGS. 1-3.

At step 910, the media device determines whether it has received an indication of a user interaction. If there is no indication of a user interaction, process 900 proceeds to step 912, and the media device determines whether it has waited a predetermined amount of time. The media device may be configured to wait a specified amount of time for a user interaction. In some embodiments, the user may indicate the amount of time the media device has to wait for a user interaction.

If the media device has not waited for the predetermined amount of time, process 900 advances back to step 908, and the media device continues waiting for a user interaction. In some embodiments, the media device may be configured to display how much time it has been waiting for a user interaction.

If, however, the predetermined amount of time has elapsed, process 900 may end at step 914. For example, the media device may automatically shut down, turn on a screen saver, enter a sleep mode or execute any other suitable function to conserve battery power.

Alternatively, if the media device receives a user interaction at step 910, the media device may verify whether the user wants to deactivate the media device at step 916. If the user wants to deactivate the media device, process 900 may end at step 914. This step may be skipped in some embodiments, or it may be a user-selectable option.

Conversely, if the user does not wish to deactivate the media device, process 900 advances to step 918, and the media device determines whether the user interaction resulted in a command that requires accessing an audio data file. For example, the user may have selected an audio data file that is being played by the media device. As another example, the user may have been presented with a list of available audio data files, and may have selected one.

The media device may receive a command to access an audio data file that is stored in memory or on another device. An audio data file accessed by the media device may be any electronic file that contains audio data. Audio data files accessed by the media device may be formatted as *.m4p files, *.wav files, *.mp3 files, *.wma files, etc. Any other suitable format may be used.

When the media device determines that it has to access an audio data file in response to the user interaction, the media device accesses the appropriate storage device and retrieves the audio data file at step 920. If the audio data file to be retrieved is available on another device, the media device may communicate with the other device using any of the communication techniques discussed above in connection with FIG. 3 so as to transfer the audio data file from the other device to the memory of the media device.

At step 922, the media device establishes whether the audio data file is associated with a metadata alter file. A metadata alter file in accordance with embodiments of the present invention may be an electronic file that contains dynamic information that can be used to alter an audio data file. In some embodiments, a metadata alter file can contain frequency value information that may be used to change the frequency value of an audio data file. In other embodiments, a metadata alter file can include data that describes a voice signature that may be applied to the text of an audio data file. An audio data file accessed by the media device may include pointers to any or all corresponding metadata alter files. A metadata alter file can also contain pointers to any or all corresponding audio data files.

If the media device determines that there are no metadata alter files associated with the audio data file, process 900 proceeds to step 924. At step 924, the media device may generate audio output signals based on the data in the audio data file. From step 924, process 900 ends at step 914.

Conversely, if the media device determines at step 922 that there is a metadata alter file associated with the audio data file, process 900 advances to step 926 where the media device retrieves the associated metadata alter file. After retrieving the associated metadata alter file, the media device may determine whether the metadata alter file includes frequency value data at step 928.

In response to determining at step 928 that the metadata alter file includes frequency value data, process 900 advances to step 930. At step 930, the media device may change the frequency of the audio data file to the frequency value in the metadata alter file. The media device may contain an oscillator which may execute step 930. After changing the frequency of the audio data file, the media device may generate audio output signals at step 932. Process 900 then ends at step 934.

Returning to step 928, if the media device determines that the metadata alter file does not include frequency data, process 900 proceeds to step 936. At step 936, the media device determines whether the metadata alter file includes voice signature data. If the metadata alter file does not include voice signature data, the media device generates a display with an error message at step 938. The message displayed may alert the user that the information needed to alter the audio data file is not available. Process 900 then returns to step 906 and the display generated at step 938 is presented to the user.

In response to determining at step 936 that the metadata alter file includes voice signature data, process 900 advances to step 940. At step 940, the media device may normalize the text of the audio data file. In some embodiments, normalizing the text may involve converting it from written form into spoken form. For example, symbols and numbers in the text may be converted into spoken form (e.g., “$500” may be converted to “five hundred dollars”). As another example, abbreviations may be converted into spoken form (e.g., “etc” may be converted to “et cetera”). Step 940 may also involve the removal of punctuation from the text, for ease of normalization.

At step 942, the normalized text from step 936 may be assigned phonetic transcriptions and converted into phoneme. At step 944, the phoneme from step 938 may be divided into speech units. The speech units may represent the speech units that will be included in the audio output signals that are generated at step 932. As an example, a sentence such as “Where does your grandmother live, Little Red Riding Hood?” may be divided into two speech units comprising “Where does your grandmother live” and “Little Red Riding Hood?.” The speech units created at step 944 may be stored in a queue in the metadata alter file.

After dividing the normalized text into speech units, process 900 proceeds to step 946, and the media device selects the next speech unit in queue. At step 948, the media device may determine whether all the speech units in the queue in the metadata alter file have been selected. If all the speech units have been selected, process 900 ends at step 934. If there is at least one speech unit that has not been selected, process 900 advances to step 950. At step 950, the media device may apply the voice signature data in the metadata alter file to the selected speech unit. After applying the voice signature data to a speech unit, audio output signals of the speech unit may be produced at step 932. Process 900 then ends at step 934.

Various speech recognition and speech synthesis systems may be used to execute process 900. For example, Apple Mac™ computers marketed by Apple Inc., contain speech recognition and speech synthesis technologies that may be used to perform process 900. Additionally, in some embodiments, the media device may be coupled to another device, which may perform one or more of the steps in process 900.

Returning to step 918, if the user interaction received at step 910 does not require data from an audio data file, process 900 proceeds to step 952. At step 952, the media device determines whether the user interaction includes a record request.

If the user interaction does not include a record request, the media device may generate a display based on the user interaction at step 954. As an example, the media device may generate a display that asks if the user would like to provide another user interaction.

If the user interaction includes a record request (e.g., the user selected my voice option 606, FIG. 6), process 900 advances to step 956, and the media device may activate one or more input components or devices. For example, the media device may activate the input components and devices discussed above in reference to FIGS. 1-3.

After activating the input component(s) or device(s), the media device may capture the voice signals the user wishes to record as an analog signal at step 958. At step 960, the media device may convert the analog signal into a digital signal and may store the digital signal as an audio data file. The media device may also create and save one or more metadata alter files in memory. A metadata alter file may include one or more data fields which may store variable information. The variable information may describe data that can be used to alter an audio data file (e.g., data that describes a voice signature).

At step 962, the media device may select the next variable listed in the corresponding metadata alter file. At step 964, the media device may determine whether all the variables in the metadata alter file have been selected. If all the variables have been selected, process 900 ends at step 966.

If at least one variable has not been selected, process 900 advances to step 968, and the media device generates a variable value for the selected variable. The media device may include any suitable mechanism for determining variable values. As an example, the media device may include a counter (not shown) that may measure the speech rate of a digital signal. Other suitable mechanisms may be used to measure other variables. Next, the media device may store the variable value in the appropriate data field in the metadata alter file at step 970. Process 900 then returns to step 962, and the media device selects the next variable in the metadata alter file.

The processes discussed above are intended to be illustrative and not limiting. One skilled in the art would appreciate that steps of the processes discussed herein may be omitted, modified, combined, and/or rearranged, and any additional steps may be performed without departing from the scope of the invention.

In the processes described above, the media device may store audio data files in memory. FIG. 10 shows an example audio data file 1000 in the form of an XML file. Any other suitable format may be used to define audio data file 1000. Audio data file 1000 may be associated with filename 1002, which may uniquely identify audio data file 1000. For example, filename 1002 uniquely identifies audio data file 1000 as the Little Red Riding Hood audio data file. Body 1004 of audio data file 1000 may include one or more tags that describe audio data file 1000. Examples may include the “name” tag (specifying the audio data file name), the “file size” tag (specifying the file size), and the “sampling frequency” tag (specifying the sampling frequency).

The start and end times of the audio data file may also be specified in “start” and “end” tags respectively. If sections of the audio data file belong to a same category, tags may be used to identify these sections. As an example, an audiobook audio data file may contain categories that correspond to the characters in the audiobook. The “Little Red Riding Hood” category might, for instance, define the sections of the audio data file that contain the voice of the Little Red Riding Hood character. Tags may be used to define the start and end times of each section that belongs to a category. For example, “LRRH_start_n” and “LRRH_end_n” tags may identify the start and end times of the nth section of the “Little Red Riding Hood” category.

Body 1004 of audio data file 1000 may also include an indication of the sections of the audio data file that a user wants to alter. As an example, tags “alter_start_n” and “alter_end_n” may signify the start and end times of the nth section of the audio data file that a user wants to alter. If a user selects a section of the audio data file to alter, the media device may create tags in audio data file 1000 to specify the section that has been selected. Body 1004 may also include a pointer that identifies a metadata alter file that is associated with the audio data file. As example, the tag “alterfile_section_n” may designate the metadata alter file that is associated with section n of the audio data file.

In some embodiments, a user may provide the input for both tags “alter_start_n” and “alter_end_n”. For example, a user may use the media device to supply the media device with the start and end times of selected audio data files. In other embodiments, an audio data file may contain a first tag that labels the beginning of the audio data file as the beginning of a user-selected audio data file (e.g., the “alter_start_n” tag). While a user is playing the audio data file, the user may instruct the media device to establish a second tag to indicate the end of the user-selected audio data file (e.g., the “alter_end_n” tag).

A user may use different techniques to select an audio data file. In some embodiments, a user may be presented with a list of available audio data files prior to playing an audio data file. The user may select an audio data file by instructing the media device to establish one or more tags the audio data file. The media device may establish tags in an audio data file to indicate the start and end times of a selected audio data file (e.g., “alter_start_n” and “alter_end_n” discussed above). In other embodiments, a user may select an audio data file as an audio output of the audio data file is being produced. For example, while a user is playing an audio data file, the user may instruct the media device to establish one or more tags in the audio data file. The media device may establish tags in an audio data file to indicate the start and end times of a selected audio data file (e.g., “alter_start_n” and “alter_end_n” discussed above). If a user decides not to select an audio data file, the user may also instruct the media device to remove one or more tags previously created in the audio data file.

In addition to audio data files, the media device may also store metadata alter files in memory. FIG. 11 shows data structure 1100 of a metadata alter file. Although data structure 1100 takes the form of a table in the example of FIG. 12, any other suitable data structure may be used in other embodiments. Data structure 1100 may include a tag column 1102 and one or more corresponding speech unit value columns. A speech unit may be defined as a word, a phrase, a sentence or any other suitable speech entity. As an example, data structure 1100 contains n speech unit value columns corresponding to the n speech units stored in the metadata alter file.

Tag column 1102 may contain suitable variables that may be used to define the voice signature. For example, tag column 1102 may include variables such as pitch, speech rate, tone, frequency, timbre and intonation. Tag column 1102 may contain any other suitable variable that may be used to characterize the voice signature. Data structure 1100 may include speech unit 1 value column 1104, speech unit 2 value column 1106 and speech unit n value column 1108. The speech unit value columns may include the corresponding unique values associated with the variables listed in tag column 1102. As an example, speech unit 1 value column 704, speech unit 2 value column 1106 and speech unit n value column 1108 may include the values 220 Hz, 302 Hz and 192 Hz for the pitch of speech unit 1, speech unit 2 and speech unit n respectively. As another example, the speech rates of speech unit 1, speech unit 2 and speech unit n may be recorded as 112 words/minute, 120 words/minute and 135 words/minute respectively.

The above described embodiments of the present invention are presented for purposes of illustration and not of limitation, and the present invention is limited only by the claims which follow. 

What is claimed is:
 1. A method for producing altered audio output signals, comprising: receiving a selection by a user of an audio data file; loading a text representation of the selected audio data file; providing a first voice signature and a second voice signature; identifying a first speech unit in the text representation, wherein the first speech unit is less than the entire text representation and is associated with dialogue of a first character in the text representation; receiving instructions to apply the first voice signature to the first speech unit; identifying a second speech unit in the text representation associated with dialogue of a second character in the text representation, wherein the audio data file comprises one or more tags that define start and end times of dialogue segments associated with respective characters in the audio data file; and applying the first and second voice signatures to the first and second speech units, respectively, to produce audio for playback.
 2. The method of claim 1, further comprising playing the audio to a user.
 3. The method of claim 1, wherein the first voice signature corresponds to a pre-recorded voice.
 4. The method of claim 1, wherein the first voice signature corresponds to a voice signature of a user.
 5. The method of claim 4, wherein the voice signature of the user is generated by: recording an audio input; and extracting data defining the voice signature of the user from the recorded audio input.
 6. The method of claim 1, further comprising, prior to loading the text representation, generating the text representation from the audio data file.
 7. The method of claim 1, wherein the first voice signature is generated from the audio data file.
 8. Apparatus for producing altered audio output signals, comprising: one or more processors and memory storing one or more programs configured for execution by the one or more processors, the one or more programs comprising instructions for: receiving a selection by a user of an audio data file; loading a text representation of the selected audio data file; providing a first voice signature and a second voice signature; identifying a first speech unit in the text representation, wherein the first speech unit is less than the entire text representation and is associated with dialogue of a first character in the text representation; identifying a second speech unit in the text representation associated with dialogue of a second character in the text representation, wherein the audio data file comprises one or more tags that define start and end times of dialogue segments associated with respective characters in the audio data file; receiving instructions to apply the first voice signature to the first speech unit; and applying the first and second voice signatures to the first and second speech units, respectively, to produce audio for playback.
 9. The apparatus of claim 8, wherein the first voice signature corresponds to a voice signature of a user.
 10. The apparatus of claim 9, further comprising instructions for generating the voice signature of the user by: recording an audio input; and extracting data defining the voice signature of the user from the recorded audio input.
 11. The apparatus of claim 8, wherein the first voice signature corresponds to a voice signature of a user.
 12. A non-transitory computer readable storage medium containing at least one computer program, the at least one computer program comprising instructions for: receiving a selection by a user of an audio data file; loading a text representation of the selected audio data file; receiving a first voice signature and a second voice signature; identifying a first speech unit in the text representation, wherein the first speech unit is less than the entire text representation and is associated with dialogue of a first character in the text representation; identifying a second speech unit in the text representation associated with dialogue of a second character in the text representation, wherein the audio data file comprises one or more tags that define start and end times of dialogue segments associated with respective characters in the audio data file; receiving instructions to apply the first voice signature to the first speech unit; and applying the first and second voice signatures to the first and second speech units, respectively, to produce audio for playback.
 13. The non-transitory computer readable storage medium of claim 12, wherein the first voice signature corresponds to a voice signature of a user.
 14. The non-transitory computer readable storage medium of claim 13, further comprising instructions for generating the voice signature of the user by: recording an audio input; and extracting data defining the voice signature of the user from the recorded audio input. 